Pistachio rootstock named ‘UCB1-D110’

ABSTRACT

Disclosed is a new and distinct variety of pistachio rootstock called ‘UCB1-D110’ characterized in that, when compared to the industry standard ‘UCB1-D1’ rootstock, it has greater growth and tolerance to the soil salts of sodium sulfate and sodium bicarbonate; greater growth and tolerance to high levels of dissolved salts in irrigation water; and earlier vegetative bud break.

Latin name: Pistacia atlantica×Pistacia integerrima.

Varietal denomination: ‘UCB1-D110’.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present variety was developed as part of a breeding program whichproduced the following pistachio rootstocks ‘UCB1-D90’ (Ser. No.14/756,672), ‘UCB1-D71’ (Ser. No. 14/756,673), and ‘UCB1-D154’ (Ser. No.14/756,676).

BACKGROUND OF THE NEW VARIETY

The present invention comprises a new and distinct cultivar of hybridpistachio Pistacia atlantica (not patented)×Pistacia integerrima (notpatented) used as a rootstock known by the varietal name ‘UCB1-D110.’The variety ‘UCB1-D110,’ is an in vitro, single selection of thesegregating controlled cross of (P. atlantica×P. integerrima) made atDavis, Calif. The purpose of the selection program was to developrootstocks with superior tolerance to soil salts. Seedlings were testedin salt trials in the laboratory and compared to the ‘UCB1-D1’ (notpatented) rootstock. Those seedlings that exhibited high tolerance tovarious soil salts were selected. The new variety exhibits hightolerance to numerous, common salts found in the soil and irrigationwater. The present variety has higher resistance to Verticillium diseasethan the female parent, Pistacia atlantica; and has higher coldtolerance than the male parent, Pistacia integerrima.

The following characteristics distinguish ‘UCB1 -D110’ from the industrystandard, ‘UCB1-D1’ (not patented) rootstock:

-   -   1. Greater growth and tolerance to the soil salts, sodium        sulfate and sodium bicarbonate.    -   2. Greater growth and tolerance to high levels of dissolved        salts in irrigation water.    -   3. Earlier vegetative bud break.    -   4. The present variety differs from rootstocks UCB1-D71,        UCB1-D90, and UCB1-D154 in that the present variety is more        tolerant to the soil salt sodium bicarbonate than the other        three varieties and UCB1-D1 (not patented).

ORIGIN AND ASEXUAL REPRODUCTION OF THE NEW VARIETY

Asexual reproduction of the new and distinct variety of rootstock wasaccomplished by germinating seed in vitro under aseptic conditions andpropagating the resulting seedlings using micropropagation techniques.Shoot epicotyl and hypocotyl tissue were collected from germinatingseedlings and placed on a standard growth media to produce shoots. Theshoots were sub-cultured and multiplied until desired numbers wereobtained and then transferred to standard rooting media for rooting.Rooted plantlets were transferred to a peat:perlite media in acclimationchambers under 100% humidity. Field environmental parameters weregradually introduced to harden plantlets which were then successivelytransferred to larger pots in the greenhouse as their size increased.These potted trees were used to establish field performance trials.Subsequent evaluations have shown those asexual reproductions aretrue-to-type to the original rootstock selection. All characteristics ofthe original tree were established and appear to be transmittedcompletely through succeeding asexual propagations.

SUMMARY OF THE NEW VARIETY

The ‘UCB1-D110’ rootstock is characterized by its tolerance to highlevels of the soil salts, sodium sulfate, and sodium bicarbonate. Ineach case, clone ‘UCB1-D110’ had greater growth in laboratory salttrials than the industry standard rootstock, ‘UCB1-D1’ (not patented).In another laboratory salt trial, media was supplemented with the totalsalt load detected in saline San Joaquin Valley irrigation water andalso supplemented with twice that load. In all cases, growth of‘UCB1-D110’ outperformed that of ‘UCB1-D1’ (not patented) in thepresence of high salts. In addition, vegetative bud break of ‘UCB1-D110’was observed to be approximately 2 days earlier than ‘UCB1-D1’ (notpatented).

DESCRIPTION OF THE ILLUSTRATIONS

The accompanying photographic illustrations show typical specimens ofvegetative growth of the new variety, with the color being as nearlytrue as is possible with color illustrations of this type:

FIG. 1 shows a 4 year pistachio tree of the new variety.

FIG. 2 shows a close-up of the mature leaves of the new variety.

DESCRIPTION OF THE NEW VARIETY

The following detailed description sets forth the characteristics of thenew variety. The data which defines these characteristics was collectedunder natural daylight on plants grown in the central valley ofCalifornia in Stanislaus County in the greenhouse and in the field.Descriptions may vary in slight detail due to climatic, soil andcultural conditions under which the variety may be grown. Colordesignations are presented with reference to the Inter-Society ColorCouncil, National Bureau of Standards, except where common color namesare also included.

TREE

-   Trunk circumference 1 foot off the ground is 27.4 cm.-   Trunk lenticels are approximately 2.9 mm in length and 0.9 mm in    width.-   Trunk lenticels are linear in shape.-   Trunk lenticel color is strong brown [55. s.B].-   Trunk lenticels number approximately 43 per square inch.-   Bark color is dark grayish yellow [91. d.g.Y].-   Branch lenticels are approximately 1.6 mm in length and 1.0 mm in    width.-   Branch lenticels are elliptic in shape.-   Branch lenticel color is strong brown [55. s.B].-   Branch lenticels number approximately 45 per square inch.

VEGETATIVE BUDS

-   Size: Approximately 43 mm in length and 4 mm in width.-   Shape: Conical.-   Color: Brilliant, yellowish green [130. b.y.G] with strong, orange    yellow [68. s.OY] exterior basal scales. As tips unfurl they become    strong purplish red [255. s.p.R].-   First vegetative buds of ‘UCB1 -D110’ opened approximately 2 days    earlier than UCB1-D1’ (not patented).-   Leaflet blade color on the top and bottom surfaces is vivid red [11.    v.R]. At the junction of the base of the petiole with the rachis,    tissue color is brilliant, yellowish green [130. b.y.G].-   Expanding rachis color is brilliant, yellowish green [130. b.y.G] at    the extreme tip and very dark purplish red [260. v.d.p.R] on all    sides elsewhere.-   Leaf venation pattern is pinnate and alternate. Midrib and veins are    brilliant, yellowish green [130. b.y.G].

FOLIAGE

-   Leaves are pinnately compound composed of alternate leaflets    numbering between 10 and 19.-   Compound leaf size variations are great but average approximately 57    cm in length and 41 cm in width at the widest point.-   Young leaflets are glossy and dark grayish red [20. d.g.R] on upper    surfaces and moderate olive green [125. m.OG] on lower surfaces.    Older leaflet surfaces are strong olive green [123. s.OG] on upper    surfaces and moderate olive green [125. m.OG] on lower surfaces.-   Leaflet shape is lanceolate with an acute apex and cuneate base.-   There is great variation in leaf and leaflet size depending on the    time of the season, position on the tree and tree age. Leaflet size    varies considerably but averages 78 mm in length and 26 mm in width.-   Leaflet venation pattern is pinnate and venation is brilliant    yellowish green [130. b.y.G]. The midrib is prominent and in very    young tissue is dark grayish red [20. d.g.R] becoming brilliant    yellowish green [130. b.y.G] as tissue becomes older.-   Leaflet margins are entire and surfaces are glabrous.-   Petiole and rachis upper and lower surface colors are the same which    is predominately strong purplish red [255. s.p.R] with some strong    yellowish green [131. s.y.G] streaking on lower surfaces.-   Petiole length varies considerably but averages 47 mm in length from    point of rachis attachment to basal leaflet, and is glabrous with no    wings.-   Rachis length varies considerably and averages about 43 cm in    length.

SALT TOLERANCE

Different concentrations of individual salts that contribute to soilsalinity and alkalinity ranging from 0 to 10,000 mg/l were added to theculture medium that rootstock was growing in. Each clone-saltcombination was replicated four times. Observations were taken on visualinjury symptoms and growth measured by number of shoots and leaves perplant. ‘UCB1-D110’ rootstock is characterized by its tolerance to highlevels of the soil salts, sodium sulfate (at 10,000 mg/l) and sodiumbicarbonate (at 1,000 mg/l). As measured on a growth scale of 1 to 10,in the case of each of these salt trials ‘UCB1-D110’ had greater growththan the industry standard rootstock, ‘UCB1-D1’ (not patented). Inanother salt trial, media was supplemented with the comparable totalsalt load detected in saline San Joaquin Valley irrigation water(Sanden, B. et al. 2009. Large-Scale Utilization of Saline Groundwaterfor Irrigation of Pistachios Interplanted with Cotton. 2009 ProgressRpt. of CA Pistachio Comm.) plus twice the detected salt load. In allcases, growth of ‘UCB1-D110’ outperformed that of ‘UCB1-D 1’ (notpatented) in the presence of high soluble salts.

DISEASE/COLD TOLERANCE

The present variety has higher resistance to Verticillium disease thanthe female parent, Pistacia atlantica.

The present variety has higher cold tolerance than the male parent,Pistacia integerrima.

Having thus described and illustrated the new variety of rootstock, whatis claimed as new and desired to be secured by plant Letters Patentis:
 1. A new and distinct variety of pistachio rootstock plantsubstantially as herein described and illustrated.